2021 Audi Q8 Coolant Identification and Mixing TSB

Audi has issued Technical Service Bulletin (TSB) 19 20 04 2025303/11, superseding previous bulletin 19-98, to provide updated guidelines on identifying and mixing engine coolants. This TSB, revised on June 25, 2020, addresses the discontinuation and mixing of Audi-approved engine coolants across a wide range of models from 1994 to 2021, including the 2021 Audi Q8. Proper coolant management is crucial for engine health and longevity.

Understanding Audi Engine Coolants

Modern combustion engines place higher demands on engine coolants, leading to continuous development and specific requirements for each type. Audi has introduced several coolant types over the years, each designed for optimal performance in specific engine generations.

Key coolant types and their introduction years include:

• G11, G12, G12+: These older coolants have been replaced by improved versions.
• G12++: Introduced in Model Year 2005 for all engines, this coolant is still available for service.
• G13: Introduced in Model Year 2008 as the initial factory fill and service coolant.
• G12evo: Introduced in Model Year 2019 as initial factory fill and service coolant.

For model year 2019 and newer vehicles, including the 2021 Audi Q8, the recommended coolant is G12evo, with part number G -12E-050-1G-DSP. For model year 2018 and older vehicles, G13 coolant, part number G -A13-774-1G-DSP, is specified. Notably, only G12evo can be used in the Audi e-tron.

Identifying Your Coolant

To determine the type of coolant currently in your vehicle, you should first identify its color. Figure 1 in the TSB illustrates the colors associated with each coolant type: G11 (green-blue), G12 (red), G12+ (purple), G12++ (purple), G13 (purple), and G12evo (purple). This visual identification is a critical first step before any mixing or servicing.

Coolant Mixing Guidelines

Audi provides a detailed chart (Figure 2 in the TSB) outlining which coolants can be mixed. This chart uses a color-coded system:

• Green: Indicates that coolants can be mixed in any ratio.
• Yellow: Indicates that mixing is possible, but it will result in a reduction of corrosion protection.
• Red: Indicates that coolants cannot be mixed.

While some coolants are compatible, it is always best practice to perform a complete coolant change rather than mixing, especially if reduced corrosion protection is a concern. An exception is G12++ and G13, which are fully compatible.

Important Warnings and Best Practices

To ensure optimal engine performance and prevent damage, Audi outlines several critical guidelines:

• Audi Q8 coolant mixing should always follow the guidelines in TSB 2025303/11.
• Only G12evo can be used in the Audi e-tron.
• Only mix distilled water with coolant additives per ElsaPro procedures.
• Deionized water must not be used.
• Drained coolant must not be reused.
• If G11 is mixed with G12+, G12++, G13, or G12evo, the coolant may turn brown, which is considered normal.

Repair Procedure Summary

If your vehicle is found to have incorrect coolant or if a coolant change is necessary due to mixing issues, the following steps should be followed:

1. Drain the system: Completely drain the coolant system using the repair manual procedures outlined in ElsaPro.
2. Rinse with water: Refill the system with water and run the engine for 15 minutes with the heater on to remove any residual coolant.
3. Final drain and refill: Drain the system again and refill it with the correct coolant to the freeze protection ratio specified in ElsaPro.

Required Tools and Parts

For accurate coolant concentration measurement, specialized refractors are needed:

• Refractor T10007B: Used to read freeze protection for G12evo coolant.
• Refractor T10007A/B: Used to read freeze protection for G13 coolant if it's unclear whether the system contains G12, G13, or a mixture.

Specific coolant part numbers are:

• G12evo: G -12E-050-1G-DSP (for MY 2019 and newer vehicles)
• G13: G -A13-774-1G-DSP (for MY 2018 and older vehicles)

Warranty Information

Audi Technical Service Bulletin 19 20 04 2025303/11 is for informational purposes only. Cooling system drain and fill procedures performed due to incorrect coolant or coolant mixing are not covered by Audi Warranty.